package com.yz.test;

import java.lang.*;
import java.util.*;

public class Java_1 {
    public static void main(String[] args) {
        System.out.print("??????n: ");
        // **********Found**********
        Scanner scan = new Scanner(System.in);
        String nstr = scan.next();
        // **********Found**********
        int n = Integer.parseInt(nstr);
        int b = 6;
        long sum = 0, item = b;
        for (int i = 1; i <= n; i++) {
            sum += item;
            // **********Found**********
            item = item * 10 + b;
        }
        System.out.print(n + "????? " + sum);
    }
}
